Viessmann VITOCAL 300-G Installation And Service Instructions Manual page 110

Installation sequence
Power supply
Two stage (type BW/BWS)
X3.7
A
X3.6
3
3
kWh
E
3/N
D
4
Shown excluding fuses and RCD.
A Heat pump control unit (for connec-
tion on cross connect PCB, see
page 225)
B Instantaneous heating water heater
(on site)
C Heat pump compressor stage 1
(type BW)
D High tariff meter
110
(cont.)
B
≈
F
4
G
C
5 4
3
kWh
3/N
H
4
E Ripple control receiver (contact
open: power-OFF enabled)
F Backup fuse ripple control receiver
G TNC system feed
H Low tariff meter
K Heat pump compressor stage 2
(type BWS)
K
4